Sewing-machine-motor controller



Feb 17, 1931. p, Q Q 1,792,816

SEWING I lACHI-NE M01011 CONTROLLER Filed Aug. 3.1927 2 $hee ts-$heet- 1 INVENTOR' ATTORNEY Feb. 17,1931. 0. H. CHASON SEWING MACHINE MOTOR CONTROLLER Filed Aug. a, 1927 2 Sheets-Sheet 2 INVENTQR ATTORNEY wnmzssgg M j Patented Feb. 17, 1931 UNITE, s'r

NT oF icEi DANIEL H. CHASON, 0F -ELIZABETH,'NEVJ JERSEY, ASSIGNOR TO THE SINGER FLA NU! FACTURING COMPANY,

JERSEY OF'ELIZABETE, NEW JERSEY, A CGRLPOR-ATION OF NEW sEwme-MAcnrnn /roren CONTROLLER Application filed August 3, 1927. Serial Ito. 210,284.

In the widespread application of electricity to the various arts, the sewing machine has received its share of attention, and various devices for the electric drive and control 5 of sewing jmachines, have been made and used. While the growing demand is for the complete, factory equipped, electric sewing machine, there are in use large-numbers of treadle-driven sewing machines which only 1e await the adventof a conveniently applicabio and usable form of motor and motor-controller to convert them into electric machines. There has already been'provided a sewing machine motor adapted for attachment-to the 5 well known family'sewing machine so as to become, in eifect,'a permanent fixture orpart of the machine, not requiring to be removed or shifted when the machineis to be put away or made ready for use. I referto the electric 2Q sewing" machine described in the U. S patent to Diehl and Hemleb No. 1,488,234, of March 25,1924. I r a The usual sewing machine motor-control-. lers areof three types, viz, handcperated, knee-operated, and foot-operated. The handoperated controlleris littleused as it interferes more-or less with the use of the operatorsha-nds in presenting and guiding the work to the sewing machines. The knee-operated controller is in more general favor, and there is practically no objection tothe foot-operated controller in so far as the broad principle of foot-operation is concerned. Foot-controllers, such as heretofore commonly'provided, have however been of the portable typecomprising a pedal operated rheostat adapted to rest upon the floor adj acent the sewingmachine table.' The diificulty with this type of foot-controller isthat tion. Furthermore, it cannot be placedin sewing machine table occupies the fio or space convenient access to the operators foot and where it would be least likely to manifest itscreeping tendency. p 4

Inthe ordinary drop-head sewing machine,

ithas a tendency to creep or shift its posiwhere the--foot, -controller; would be of most as converted to an electric-sewing machine,

by the application of an electric motor and foot-controller, the treadle mechanism of the sewing machine stand has no function exceptas a potential foot-power drive and, as above stated, the treadleeplate is in the way ofconvenient location of the foot-controller.

With the idea of using the conveniently accessible and operable treadle-plate asa means for operating the motor-controller, it has been proposed to mount the motor-controller or rheostat on the sewing machine tahis and connect it by a pull-rod to the treadle-plate, but n'one of the devices heretofore proposed fills the long-felt want for a treadleplate operated motor-controller which may, be readily applied to or removed from the usual sewing machine table by one not possessed of mechanical skill, and which is of simple and dependable construction. and of neat and inconspicuous appearance.

The present inventionhas for an object to provide a motor-controller to fill the want referred .to and enable the well-known treae. v

dle-driven family sewing. machine to be.

readily converted into an electricmachine.

J .L'l.

. the legs of the usual cast-iron sewing machine stand. This bracket, when attached to the brace member in question, presents an up standing base surface upon VVilCll the controller unit maybe mounted in two different angularly related positions; The controller unit, per se, 1s of well-known construction embodying a variable resistance unit and a' rock-shaft for operating such unit; the mounting provisions being such that the rock-shaft may be disposed .horizontaliy'or in an up-and-down'position. Then disposed horizontally, the rock-shaft may-have secured there-to a crank-arm. from the free end of which hangs a pitman-section adapted to be connected to the lower section of the usual .7 A further object or tne'invention is to provide a motor-controller which is readily, adaptable for eitherfoot or knee operation.

treadle pitman-rod, for foot operation. "When disposed vertically, the rock-shalt may have secured to it a knee-shift lever extending forwardly to a position for convenient knee operation. By mounting the rock-shaft operated controller unit on the brace member of the usual cast-iron sewing machine stand, it is located in a peculiarly advantageous position where it is adaptable for either foot or knee operation with maximum of convenience and a minimum oi": ap nirtenances.

In the accompanying drawings, l is a front side elevation of a sewing machine embodying the invention. Fig. 2 is a sectional view on the line 22, i. Fig. 3 is a detail view of the upper end of the treadle pitman-rod. Fig. 4 is a detail view 01" the crankstrap to which the treadle pitman-rod is connected for toot-power operation. 5 is a detail view of the controller hook-member to which the pitman-rod is connected for electrical operation. 6 is a front elevation of the iron frame-work or" a sewing machine stand to which the motorcontroller is attached and converted for knee operation. F 7 is a top plan view of the stand shown in Fig. 6. Fig. 8 is a perspective view of the controller converted for foot operation. F ig. 9 is a similar view f the controller as con-- verted for knee operation. Fig. 10 is a top plan view of the variable resistance unit of the controller. Fig. 11 is aside view of the latter with the cover shown in section. Fig. 12 is a section on the line 12--12, Fig. 10, and Fig. 13 is a perspective view of the cover element of the controller.

According to the preferred embodiment of the invention illustration, Fig. 1 represents a well-known family machine of the drop-head type comprising a sewing head 1 seated upon the wooden top 2 carried by the cast-iron. frame-work including the end legs 3 and intermediate spacer or brace-member The brace-member 4 has mounted thereon the usual treadle-plate 5 and crankshaft 6 carrying a belt-wheel 7 which. for foot-power operation, is connected by the belt 8 to the usual grooved balance-wheel 9 of the sewing machine.

The crank-shaft 6 is embraced by the crankstrap 10 which, for foot-power operation, is connected to the usual treadle-rod or pitman 11, as shown in Fig. 6; the crank-strap 1O constituting, in effect, an upper pitinan se tion or extension of the pitman 11. The pitman 11 has the usual ball-and-socket connection at its lower end 12 with the treadle-plate 5 and is threaded at its upper end 13 to screw into the threaded socket 14, F 4, 0?."- the erank-strap 10.

For electrical operation, the belt 8 is removed from the balance wheel 9 and a motor 15, such for example as that shown in said Diehl and Hemleb patentis applied to the sewing head and connected by the belt 16 to the balance-wheel 9. The motor 15 is connected to the source of electrical energy by the supply cord 17 in series with the cord 18 leading to the motor-controller 19 which, in the present instance, is a variable resistance device mounted on the braee-n'iembcr 4 and including an operating rock-shaft 20 carrying a crank-arm 21 to the apertured free end of which is connected a hook 22 having the threaded socket 23, Fig. 5, for reception of the threaded end 13 of the pitman-ro-d 11. As thus connected for electrical operation, pressure upon the treadie-platc 5 cil'ects a rocking movement of the controller rock-shaft 20, which effects a variation of the resistance in the motor-circuit and enables the speed of the motor 15 and machine 1 to be nicely controlled.

lVhile the motor-controller 19 may be of any desired type, it is preferred to employ a variable resistance unit such as disclosed in the Patent to D. H. Chason, No. 1,643,292, of September 27, 1927. This variable resistance device comprises a supporting base 24 for a well-known type of compression rheostat, having a porcelain body 25 formed with a pair ofwells 26, which are substantially filled with stacks 2. of resistor disks of carbon, graphite, or the like. Terminals 28 are provided at one end of each stack of disks 27 and a terminal pressure head 29 is provided at the opposite end of each of such stacks. Slidably mounted in the porcelain body is the rheostat operating rod 30, one end of which carries the insulating bushing 31 passing through the apertured arm 32 of the bell-crank lever 32, 33 fulcrumed at 34 on the base 24. The rod 30 carries at its'other end the leaf-spring bridging contact member 35 and the stiii'er backing member 36 which apply the variable working pressures to the carbon disks when the rod 30 is moved endwise. The coil-spring 37 retains the bushing 31 in working engagement with the arm 32 of the bell-crank lever. The operating rock-shaft 20 is journalled in the bearing bushing 38 in the upstanding wall 39 at one end of the base 24 and has fixed to its inner end the cam-plate 40 having the cam-edge 41 in working engagement with the arm 33 of the bell-crank lever. The camplate 40 is also formed with stops 42 which limit its rocking motion by engagement with the base 24. The coil-spring 43 urges the cam 40 and rock-shaft 20 to oil or nonrunning position. A sheetanetal cover 44 is applied to the base 24 to encase the resistance unit. This cover has retaining lips 45, 46, under-lapping the base 24; there being a fastoning screw passed through the lip 46 to hold the cover securely in position.

To mount the controller on the brace-member 4 there is provided an adapter 47, Fig. 8, comprising a plate having a pair of overhanging hooks 49 at its upper edge. Adjustably secured to the adapter 47 by the screw gripping the central horizontal bars 55 of the brace-member. The plate 51 lies between the spaced rests 51 which bear againstthe rear side of the brace-member when the hook is fastened in clamping position;

It will be noted that the base 24 has two threaded screw holes 56, while the adapter plate 47 has two similarly spaced but non threaded holes 57 through which fastening screws 58 are passed into the base 24 to secure the controller to the adapter-plate 47 with its rock-shaft 20 disposed horizontally, Fig. 8. The plate 47 is also preferably provided with a third screw-hole59, through which and the upper of the screw holes '57, the

screws 58 may be passed into the threaded holes 56 in the base 24 to secure the controller in a position turned90 from its previously described position, or with its rock-shaft 20 disposed in an upstanding position for reception of a knee-shift lever 59 which extends forwardly, Fig. 7 to a position within comfortable reach of the operatorsknee. 7

By mounting the controller 19 on the brace member 4, and particularly at the rear of brace-member 4, it is located in a position particularly advantageous for easy conversion from foot to knee operation and vice versa. It is also located in aposition'where its connection with the usual 'treadle pitmanrod maybe effected with great simplicity.

Still further, it is not in a conspicious posi tion and, together with its. cord 18, is well off of the floorand out of the way.

Having thus set forth the nature of the invention, what I claim herein is 1. The combination with a sewing machine adapted to grip the upper and lower horizontal bars of the brace-member of the usual cast-iron sewing machine stand.

3. A convertible foot or knee operated motor-controller comprising a variable resistance unit having an operating rock-shaft, a bracket adapted for mounting on the bracemember of the usual cast-iron sewing machine stand, and means for securing said resistance unit to said bracket in either of two angularly related positions in one of which the rock-shaft is adapted for connection to the treadle-plate of the sewing machine stand and in the other of which the rock-shaft is adapted to carry a knee-shift lever.

In testimony whereof, I have signed my name to this specification.

DANIEL H. CHASON;

stand having the usual end legs, intermediate brace-member, belt-wheel, belt-wheel supporting crank-shaft, and treadle, of a motorcontroller unit having an operating rockshaft and means for mounting such unit on and at the rear of such brace-member with said rock-shaft disposed horizontally and extending toward said belt-wheel, a crank-arm on said rock-shaft, and a multi-sectioned pitman, the lower of which is the usual pitman- 2. A sewing machine motor-controller comprising a variable resistance unit, a casing for said unit, separable 7 upper and lower- 7 clamping fingers connected to said casmg and 

